Apparatus for identifying x-ray films



Nov. 19, 1940. M. B. EVANS APPARATUS FOR IDENTIFYING X-'RAY FILMS FiledSept. 14, 1938 ZShBetS-Sheet 1 Ill \ HllllllllllllLlllllllll] R M mM n lV N F NE, R NE E Q om W5 n UN l M RGV FIN. 4 um MB K mm WM .M SE mw DIAPPARATUS FOR IDEN'VIIFYING X-RAY FILMS Filed Sept. 14, 1938 2Sheets-Sheet 2 salme-120710 |NVENTOR /MY/vx afl/4M; b5 v B nl VW@ATTORNEY m. Ell? JEC'- hantail Nev. is, 1940 f UNITED STATES APPARATUSFoa mEN'rrrYING x-RAY FILMS l Maynard B. Evans, Detroit, Mich., assignorto Westinghouse X-Bay Company, Inc., Long Island City, N. Y., acorporation of Delaware Application September 14, 1938, Serial No.229,927

2 Claims.

photographs and particularly to an apparatus for marking the X-ray filmsfor the purpose of subsequent identification by what is known assolarizing.

At the present time the roentgenologist usually identifies theX-rayiilms of a patient by the utilization of file numbers placed on thefilm during exposure of the patient, so that such numbers appear on thedeveloped film. However,

such method of identification is inevitably subvject to error and thisfact is so well appreciated that X-ray films so identified are notaccepted in the courts as direct positive proof of identii5 fication ofany particular patient, which requires considerable corroborating andconvincing testimony before acceptance of a film as being that l of apatient in question.

It has also been proposed in the art to obviate 2t the possibility oferror and to make an X-Tay film more positive for identification.purposes by enabling a patient to identify his film by autographing sothat the signature appears upon the developed film. To enable films tobe identified 25 in this manner 'the cassette which houses theundeveloped film is provided with a window so that the patient mayimpress his signature upon the film by the use of a stylus for writingupon the protective covering of the film.

Again, however, this manner of identification is by no means infallible,since upon developing the film the signature appears thereon in theusual negative form which would enable the 45 films so as to identifythe film as that of a particular patient .by solarizing the film afterthe patient has autographed the same so that the film is not onlypositively identified as being that of such patient, but the identifyingmark or sig- 50 nature cannot be transferred to any other film withoutsuch` transfer being immediately discernible.

Another object of the present invention is the provision of an apparatusfor solarizing a pore tion oi' a photographic film bearing the signa-'rhis invention relates to the taking of x-ray ture of a patient so thatthe film can be readily identified as being that of a particular patientand which prevents the transfer of the autograph or other marking of thepatient to another film without such fiaw being immediately determined.5 v Still further objects of the present invention will become obviousto those skilled in the art by reference to the accompanying drawingswherein:

Fig, 1 is a perspective view of a patient in po-Y 1 sition for aradiographic exposure of the hand;

Fig. 2 is a plan view of a cassette for housingK a sensitizedphotographic film and which is provided with a Window to enable the filmto be marked by the patient autographing the film;4

Fig. 3 is a fragmentary plan view on an enlarged scale of the cassetteas shown in Fig. 2 after the patient has autographed the film;

Fig. 4 is a cross-sectional view taken on the line iV-IV of Fie. 3;

Fig. 5 is a perspective View looking at the front of a solarizingapparatus made in accordance with the present invention; y

Fig. is a fragmentary view of the film -after solai-ization anddeveloping thereof;

Fig. 'l is a lsectional view of the solarizing appa= ratus Shown inVFig. 5 and taken on the -line VIL-VU of Fig. 3;

Fig. 8 is a sectional view of the solarizing apparatus Shown in Fig. 5and taken on the line VIII-VIH of Fig. 7;

Fig. 9 is a sectionalview of the solarizing apparatus shown in Fig- 5and taken on the line m-IX ofFig. 'Z with a portion of the apparatusbroken' away to `better illustrate the apparatus;

Fig. 10 is a schematic diagram of the electrical, circuit lof thesolarizing apparatus, and y Fig. 11 is a graphic illustration of thefilm exposure producing solarization.

Referring nowto the drawings in.detail, in Fig. 1 a patient is shown inposition for the taking of a radiographic exposure of the hand. Asuitable support such as a table top 5 is shown Supporting a cassette 8containing the sensitized photographic film. The hand of the patientrests upon the cassette and an X-ray tube 'l is positioned above thehand of the patient and the cassette a. suitable distance. 'The X-raytube is then energized with a resulting exposure of the film within thecassette B, as is customary in the 50 art.

The cassette, as will be seen in Figs. 2, 3 and 4, is provided with anopening or window 8 which exposes a portion of the sensitized surface ofthe film. In orderI to identify the film, the patient, 55

Fig. 3.

The cassette i may be of any type well known in the art and, as shown,comprises a metallic frame 9 having slots I0 and I2 which receive thefront panel Il, usually composed of a phenolic condensation product,such as Bakelite, and a spring member Il retains the removable backplate I5 in position so that a felt cushion or the like i8 presses thesensitized film I1 iirmly against the front panel Il. f

Sometimes it is desirable in the taking of radiographic exposures -i'cemploy intensifying screens, such as shown at Il, between which thesensitized film is disposed. If it is desired to employ such screens.the screen next tothe front panel is provided with an opening of thesame contour as the opening 8 in the front panel. but of slightlysmaller dimensions, and the opening thus provided in the intensifyingscreen may be` edged with adhesive material, such as tape or the likei9, to increase pressure on the illm around the opening in theintensifying screen so that light is precluded, from falling on thesensitized nlm except over the area exposed through the opening.

After exposure of the illm to X-rays and the fixing of the patientsautograph to the portion which has been exposed to daylight, thecassette, as is customary, is taken to the dark room. In

-Ililgs. 5 to 10, inclusive, a solarizing apparatus` forming the subjectmatter of the present invention is shown, which is disposed in thedarkroom so that the film can be placed therein prior to development. Thisapparatus comprises a casing 2i which may be supported by suitablepedestals 22 and a'hinged cover 22 is secured to the casing.

As will be noted more clearly from Figs. 'l' and 8 the hinged cover isprovided with a pair oi pivots 24 to which links 25 are pivotallyconnected and I which pivotally support a handle 26. A pair of angularlink members 21 have one end thereof also pivotally connected to thehandle 2l and their opposite ends are pivotally secured to the pedestals22, as canbe more readily seen in Fig. '7.

In order to raise the cover 23 of the solarizing apparatus, the handle28 is pushed rearwardly,

the cover and the casing until the nlm contacts' a ridge 28 to preventfurther insertion of `the The top of the casing 2| is provided with anopening or window 29 surrounded by an oval ridge 30. When the nlm isinserted between the cover and the casing against the ridge 2l, the filmis thus positioned so that the portion thereof bearing the autograph ofthe patient, and which has been pre-exposed to daylight, aligns with thecasing window 29. v I Enclosed within the casing 2 i is an incandescentlamp 32A of about 250 watts adapted to be energized from the customarysource of electrical energy of domestic potential Li, L2 (Fig. l0).

A microswitch. as itis termed, ll is molmted on the underside of thecasing top and the hinged cover 28 is provided with a pin orthe like upro- Jecting through an opening 3l in the casing top which engages themicro-switch 22 to cause clol sure of its contacts.

As will be noted from Fig. lp, a mercury switch It is also connected inseries relation with the lamp and micro-switch Il. This mercury switchis mountedln a cradle support 31 pivotally se- 10 cured to the side ofthe casing and provided with an angular arm Il which contacts one of thelink members 21, and biasing springll' is connected \`groove 42 which isengaged by the ridge )il of u' the casing top to pinch the film andprevent the spread of light over the film other than the area of thewindow 28.

Upon closure of the hinged cover 23 the pin Il projects through theopening Il and closes the o contacts of the micro-switch 32. Since theangular link 21 contacts the angular arm I8, the cradle support 31 isrocked, moving the mercury switch 2B from its open position, as shown inFig. l0, to the closed position as shown in dotted 35 lines in Fig. 8,thus placing the spring 28 under tension and closing the circuit to thelamp 22.

'I'he lamp 22 accordingly becomes illuminated and exposes the alreadypre-exposed autographed portion of the illm with the spread of the light4o being precluded by the pinching of the illm. as before noted. by theridge 20 vancl groove 42, and at the same time the illumination of thelamp can be observed through a bulls-eye disposed on the front of thecasing 2l. The construction of the mercury switch u is such that ittakes the mercury pool approximately seventeen seconds to ilow from oneend of the switch to the other, thus opening the contacts toI extinguishthe lamp l2. and such fact being observed by the operator through themedium of the fbull's-eye I2, the l film is ready for removal from thesolarizer and development. When the handle is pushed rearwardly, asabove noted, to raise the cover, the tension of the spring 38 causes thecradle support 5s 31 to rock in the oppomte direction to the positionshown in Fig. l0, allowing the mercury to flow to the opposite end oi.'the switch 28 and, while again closing its contacts during the flow,

the lamp I2 nevertheless remains extinguished oo since the circuit isinterrupted byr the microswitch II.

During exposure of the autographed portion of the illm to the intenseillumination from the lamp I2, such portion is solarized, viz., a.reversal in the graduation sequence in the image results from thatnormally obtained on the developed film and when the solarized film isdeveloped. instead of the patients autograph being the customarynegative. the signature develops out less black tl. in the surroundingarea which, after desensitizing and washing of the .crystals of thesensitized surface, leaves a transparent signature on a slightly foggedbackground.

This may be better appreciated by reference to 7s Fig. 1l. wherein theabscissa represents iight exposure in seconds and the ordinate, densityof the developed lm. From this curve it will be noted that as the timeincreases the density increases up to a definite point on the upwardslope of the curve, as indicated by the light line, which represents thenormal exposure producing the customary negative. However, by continuedexposure to light the density reaches a maximum and falls off, againapproaching the density of the customary negative. During the exposurethere is a definite point on the curve where, due to overexposure.solarization occurs, as shown by the heavy line of the curve, and asindicated the preferable point is that between the arrows or near the-peak of the curve.

By virtue of the solarization of the autographed portion of the filmtransfers, re-printing, etc., are prevented without such fact beingimmediately discernible and even if achange is attempted`to the filmprior to solarization, it shows up after solarization and development.

'It thus becomes obvious to those skilled in the art that I haveprovided a method and apparatus or reprinting of the lms is preventedwithout such transfer or reprint becoming immediately discernible. Sinceall doubts as to the films being that of a given patient who autographsthe same are removed, such soiarized films should have` considerableevidentiary value in litigation. as welly as definitely identifying thefilms even after being led for many years.

Although I have shown and described one embodiment of the presentinvention, I do not desire to be limited thereto, as various othermodifications of the same may be made wit-hout deazeaoaa parting fromthe spirit and scope of the appended claims. v

I claim: l

1. A solarizing apparatus for identifying films comprising a casingprovided lwith a window therein, a source of illuminationl in saidcasing, a cover for said casing provided with a lining to excludeextraneous'light and operable to retain a pre-autographed undevelopedfilm in a fixed position with the autographed portion thereof inalignment with the windowin said casing, means forming ra border aroundthe window in said casing, means. carried by said cover and registeringwith said border means for said window to prevent the spread of lightfrom said source except over the autographed area of said-undevelopedfilm, and means operable to cause energization of said source ofillumination for a preselected period of time' for the purpose ofsolarizing the autographed portion of said undeveloped film prior todevelopment thereof.

2. A s'olarizing apparatus for identifying films comprising a casingprovided with a window therein, a source of illumination in said casing,a cover pivotally connected to said casing, means for moving said cover-to retain a pre-autographed undeveloped film in a fixed position withthe autographed -p'ortion thereof in alignment with the window in saidcasing, a ridge on said casing surrounding said window, a recess on saidcover aligning with said ridge to crimp said undeveloped film andprevent the spread of Vlight except over the autographed portion of saidundeveloped film, and means operable upon movement of said cover tocause energization of said source of illumination for a preselectedperiod of time for the purpose of solarizing the autographed portion ofsaid undeveloped lm by over-exposure prior to development thereof.

MAYNARD B. EVANS.

